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1.
Zygote ; 31(6): 577-581, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37905414

RESUMO

Klotho is a protein that plays different functions in female fertility. We have previously reported that klotho protein supplementation during in vitro maturation improves porcine embryo development, while klotho knockout for somatic cell cloning completely blocks full-term pregnancy in vivo. However, the effects of the microinjection of klotho protein or klotho knockdown dual vector in porcine embryos at different time points and the specific molecular mechanisms remain largely unknown. In this study, we injected the preassembled cas9 + sgRNA dual vector, for klotho knockdown, into the cytoplasm of the germinal vesicle stage of oocytes and into porcine embryos after 6-h parthenogenetic activation. Similarly, the klotho protein was inserted into the cytoplasm of germinal vesicle stage oocytes and porcine embryos after 6-h parthenogenetic activation. Compared with the controls, the microinjection of klotho dual vector markedly decreased the blastocyst formation rates in germinal vesicle stage oocytes and activated embryos. However, the efficiency of blastocyst formation when klotho protein was inserted before in vitro maturation was significantly higher than that after klotho protein insertion into parthenogenetically activated embryos. These results indicated that klotho knockdown may impair embryo development into blastocyst irrespective of injection timing. In addition, klotho protein injection timing in pig embryos may be an important factor for regulating embryo development.


Assuntos
Oócitos , RNA Guia de Sistemas CRISPR-Cas , Gravidez , Animais , Feminino , Suínos , Oócitos/fisiologia , Blastocisto , Desenvolvimento Embrionário/genética , Partenogênese
2.
Front Microbiol ; 14: 1202993, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520371

RESUMO

High-mobility group box 1 (HMGB1) is a protein that binds to DNA and participates in various cellular processes, including DNA repair, transcription, and inflammation. It is also associated with cancer progression and therapeutic resistance. Despite its known role in promoting tumor growth and immune evasion in the tumor microenvironment, the contribution of HMGB1 to the development of Kaposi's sarcoma (KS) is not well understood. We investigated the effect of HMGB1 on KS pathogenesis using immortalized human endothelial cells infected with Kaposi's sarcoma-associated human herpes virus (KSHV). Our results showed that a higher amount of HMGB1 was detected in the supernatant of KSHV-infected cells compared to that of mock-infected cells, indicating that KSHV infection induced the secretion of HMGB1 in human endothelial cells. By generating HMGB1 knockout clones from immortalized human endothelial cells using CRISPR/Cas9, we elucidated the role of HMGB1 in KSHV-infected endothelial cells. Our findings indicate that the absence of HMGB1 did not induce lytic replication in KSHV-infected cells, but the cell viability of KSHV-infected cells was decreased in both 2D and 3D cultures. Through the antibody array for cytokines and growth factors, CXCL5, PDGF-AA, G-CSF, Emmprin, IL-17A, and VEGF were found to be suppressed in HMGB1 KO KSHV-infected cells compared to the KSHV-infected wild-type control. Mechanistically, phosphorylation of p38 would be associated with transcriptional regulation of CXCL5, PDGF-A and VEGF. These observations suggest that HMGB1 may play a critical role in KS pathogenesis by regulating cytokine and growth factor secretion and emphasize its potential as a therapeutic target for KS by modulating the tumor microenvironment.

3.
J Med Virol ; 95(8): e28978, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37515534

RESUMO

Dengue virus, which belongs to the Flaviviridae family, can induce a range of symptoms from mild to severe, including dengue fever, dengue hemorrhagic fever, and dengue shock syndrome. While infectious cloning technology is a useful tool for understanding viral pathogenesis and symptoms, it exhibits limitations when constructing the entire Flavivirus genome. The instability and toxicity of the genome to bacteria make its full-length construction in bacterial vectors a time-consuming and laborious process. To address these challenges, we employed the modified infectious subgenomic amplicon (ISA) method in this study, which can potentially be a superior tool for reverse genetic studies on the dengue virus. Using ISA, we generated recombinant dengue viruses de novo and validated their robust replication in both human and insect cell lines, which was comparable to that of the original strains. Moreover, the efficiency of ISA in genetically modifying the dengue virus was elucidated by successfully inserting the gene for green fluorescence protein into the genome of dengue virus serotype 4. Overall, this study highlighted the effectiveness of ISA for genetically engineering the dengue virus and provided a technical basis for a convenient reverse genetics system that could expedite investigations into the dengue virus.


Assuntos
Vírus da Dengue , Dengue , Flaviviridae , Flavivirus , Humanos , Vírus da Dengue/genética , Genética Reversa/métodos , Flavivirus/genética , Flaviviridae/genética , Replicação Viral/genética
4.
Proc Natl Acad Sci U S A ; 120(31): e2300475120, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37494397

RESUMO

Eukaryotes organize cellular contents into membrane-bound organelles and membrane-less condensates, for example, protein aggregates. An unsolved question is why the ubiquitously distributed proteins throughout the cytosol give rise to spatially localized protein aggregates on the organellar surface, like mitochondria. We report that the mitochondrial import receptor Tom70 is involved in the localized condensation of protein aggregates in budding yeast and human cells. This is because misfolded cytosolic proteins do not autonomously aggregate in vivo; instead, they are recruited to the condensation sites initiated by Tom70's substrates (nascent mitochondrial proteins) on the organellar membrane using multivalent hydrophobic interactions. Knocking out Tom70 partially impairs, while overexpressing Tom70 increases the formation and association between cytosolic protein aggregates and mitochondria. In addition, ectopic targeting Tom70 and its substrates to the vacuole surface is able to redirect the localized aggregation from mitochondria to the vacuolar surface. Although other redundant mechanisms may exist, this nascent mitochondrial proteins-based initiation of protein aggregation likely explains the localized condensation of otherwise ubiquitously distributed molecules on the mitochondria. Disrupting the mitochondrial association of aggregates impairs their asymmetric retention during mitosis and reduces the mitochondrial import of misfolded proteins, suggesting a proteostasis role of the organelle-condensate interactions.


Assuntos
Proteínas Mitocondriais , Agregados Proteicos , Humanos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Citosol/metabolismo , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Transporte Proteico
5.
Korean J Med Educ ; 35(2): 199-205, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37291848

RESUMO

PURPOSE: This study was conducted to examine the results of designing and implementing a teaching program for medical education as the elective course for 4th-year students of medical course. METHODS: In order to design the teaching program for medical education as an elective course, we conducted literature review, five medical education experts were interviewed, and the literature required in the design process was reviewed. A developing teaching program was implemented as an elective course in a medical school of Korea, and 4th-year students of medical course participated in the program. RESULTS: In the elective course, the medical education program process competencies were derived into three categories: theoretical educational knowledge, teaching competency, and research competency for education. Moreover, instructional materials were developed to help students achieve these competencies. And project-based learning strategy was selected and implemented for 4th-year students in medical course, and positive satisfaction was confirmed. CONCLUSION: As a study designed and implemented in a medical education program in a medical school in Korea, it is expected to be helpful when introducing medical education to undergraduate students or developing a medical education program to strengthen the teaching capacity of residents.


Assuntos
Educação de Graduação em Medicina , Educação Médica , Estudantes de Medicina , Humanos , Currículo , Estudantes , República da Coreia , Ensino
6.
Autophagy ; 19(8): 2318-2337, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36843263

RESUMO

Impaired activities and abnormally enlarged structures of endolysosomes are frequently observed in Alzheimer disease (AD) brains. However, little is known about whether and how endolysosomal dysregulation is triggered and associated with AD. Here, we show that vacuolar ATPase (V-ATPase) is a hub that mediates proteopathy of oligomeric amyloid beta (Aß) and hyperphosphorylated MAPT/Tau (p-MAPT/Tau). Endolysosomal integrity was largely destroyed in Aß-overloaded or p-MAPT/Tau-positive neurons in culture and AD brains, which was a necessary step for triggering neurotoxicity, and treatments with acidic nanoparticles or endocytosis inhibitors rescued the endolysosomal impairment and neurotoxicity. Interestingly, we found that the lumenal ATP6V0C and cytosolic ATP6V1B2 subunits of the V-ATPase complex bound to the internalized Aß and cytosolic PHF-1-reactive MAPT/Tau, respectively. Their interactions disrupted V-ATPase activity and accompanying endolysosomal activity in vitro and induced neurodegeneration. Using a genome-wide functional screen, we isolated a suppressor, HYAL (hyaluronidase), which reversed the endolysosomal dysfunction and proteopathy and alleviated the memory impairment in 3xTg-AD mice. Further, we found that its metabolite hyaluronic acid (HA) and HA receptor CD44 attenuated neurotoxicity in affected neurons via V-ATPase. We propose that endolysosomal V-ATPase is a bona fide proteotoxic receptor that binds to pathogenic proteins and deteriorates endolysosomal function in AD, leading to neurodegeneration in proteopathy.Abbreviations: AAV, adeno-associated virus; Aß, amyloid beta; AD, Alzheimer disease; APP, amyloid beta precursor protein; ATP6V0C, ATPase H+ transporting V0 subunit c; ATP6V1A, ATPase H+ transporting V1 subunit A; ATP6V1B2, ATPase H+ transporting V1 subunit B2; CD44.Fc, CD44-mouse immunoglobulin Fc fusion construct; Co-IP, co-immunoprecipitation; CTSD, cathepsin D; HA, hyaluronic acid; HMWHA, high-molecular-weight hyaluronic acid; HYAL, hyaluronidase; i.c.v, intracerebroventricular; LMWHA, low-molecular-weight hyaluronic acid; NPs, nanoparticles; p-MAPT/Tau, hyperphosphorylated microtubule associated protein tau; PI3K, phosphoinositide 3-kinase; V-ATPase, vacuolar-type H+-translocating ATPase; WT, wild-type.


Assuntos
Doença de Alzheimer , ATPases Vacuolares Próton-Translocadoras , Camundongos , Animais , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Hialuronoglucosaminidase/metabolismo , Ácido Hialurônico , Fosfatidilinositol 3-Quinases/metabolismo , Autofagia , Proteínas tau/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Proteínas de Transporte , Camundongos Transgênicos , Modelos Animais de Doenças
7.
J Med Virol ; 95(1)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35869037

RESUMO

Many cytokines produced by Kaposi's sarcoma-associated herpesvirus (KSHV)-infected cells have been shown to participate in the pathogenesis of KSHV. Determination of the exact role of cytokines in Kaposi's sarcoma (KS) pathogenesis is limited, however, by the difficulty to manipulate the target genes in human endothelial cells. In this study, we sought to elucidate the role of cytokines in KSHV-infected human immortalized endothelial cell line (HuARLT cells) by knockout (KO) of the corresponding target genes using the CRISPR/Cas9 system. The cytokine production profile of KSHV-infected HuARLT cells was analyzed using a protein array, and several cytokines were found to be highly upregulated following KSHV infection. This study focused on CXCL1, which was investigated by knocked out in HuARLT cells. KSHV-infected CXCL1 KO cells underwent increased cell death compared to KSHV-infected wild-type (WT) cells and mock-infected CXCL1 KO cells. Lytic replication was not observed in KSHV-infected WT nor CXCL1 KO cells. Phosphorylation of STAT3 was significantly suppressed in KSHV-infected CXCL1 KO cells. Additionally, inhibitors of STAT3 and CXCL1 induced cell death in KSHV-infected endothelial cells. Our results show that CXCL1 production is required for the survival of KSHV-infected endothelial cells, and the CXCL1 to STAT3 phosphorylation signaling pathway may be a therapeutic target for KS.


Assuntos
Herpesvirus Humano 8 , Sarcoma de Kaposi , Humanos , Herpesvirus Humano 8/fisiologia , Células Endoteliais , Fosforilação , Citocinas/metabolismo , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
8.
Biosensors (Basel) ; 12(9)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36140123

RESUMO

Electrochemiluminescence (ECL)-based sensing systems rely on light emissions from luminophores, which are generated by high-energy electron transfer reactions between electrogenerated species on an electrode. ECL systems have been widely used in the detection and monitoring of diverse, disease-related biomarkers due to their high selectivity and fast response times, as well as their spatial and temporal control of luminance, high controllability, and a wide detection range. This review focuses on the recent strategic and technological advances in ECL-based biomarker detection systems. We introduce several sensing systems for medical applications that are classified according to the reactions that drive ECL signal emissions. We also provide recent examples of sensing strategies and technologies based on factors that enhance sensitivity and multiplexing abilities as well as simplify sensing procedures. This review also discusses the potential strategies and technologies for the development of ECL systems with an enhanced detection ability.


Assuntos
Técnicas Biossensoriais , Medições Luminescentes , Biomarcadores , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Eletrodos , Medições Luminescentes/métodos , Fotometria
9.
Biosensors (Basel) ; 12(7)2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35884335

RESUMO

Bacterial contamination is a public health concern worldwide causing enormous social and economic losses. For early diagnosis and adequate management to prevent or treat pathogen-related illnesses, extensive effort has been put into the development of pathogenic bacterial detection systems. Colorimetric sensing systems have attracted increasing attention due to their simple and single-site operation, rapid signal readout with the naked eye, ability to operate without external instruments, portability, compact design, and low cost. In this article, recent trends and advances in colorimetric systems for the detection and monitoring of bacterial contamination are reviewed. This article focuses on pathogen detection strategies and technologies based on reaction factors that affect the color change for visual readout. Reactions used in each strategy are introduced by dividing them into the following five categories: external pH change-induced pH indicator reactions, intracellular enzyme-catalyzed chromogenic reactions, enzyme-like nanoparticle (NP)-catalyzed substrate reactions, NP aggregation-based reactions, and NP accumulation-based reactions. Some recently developed colorimetric systems are introduced, and their challenges and strategies to improve the sensing performance are discussed.


Assuntos
Bactérias , Monitoramento Ambiental , Bactérias/isolamento & purificação , Colorimetria , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos
10.
Molecules ; 26(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34500620

RESUMO

Aptamers are artificial nucleic acid ligands that have been employed in various fundamental studies and applications, such as biological analyses, disease diagnostics, targeted therapeutics, and environmental pollutant detection. This review focuses on the recent advances in aptamer discovery strategies that have been used to detect various chemicals and biomolecules. Recent examples of the strategies discussed here are based on the classification of these micro/nanomaterial-mediated systematic evolution of ligands by exponential enrichment (SELEX) platforms into three categories: bead-mediated, carbon-based nanomaterial-mediated, and other nanoparticle-mediated strategies. In addition to describing the advantages and limitations of the aforementioned strategies, this review discusses potential strategies to develop high-performance aptamers.


Assuntos
Aptâmeros de Nucleotídeos/química , Nanopartículas/química , Nanoestruturas/química , Humanos , Ligantes
11.
Tomography ; 7(3): 278-285, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34449749

RESUMO

The purpose of this study was to evaluate the diagnostic accuracy of patent with ductus arteriosus (PDA) based on the availability of pretest information on routine chest CT with 3 mm slice-thickness. We retrospectively evaluated CT of 64 patients with PDA. The enrolled patients were categorized as group 1 (presence of pretest information) and 2 (absence of pretest information, silent PDA). CTs were read by eleven board-certified radiologists, and subsequently by two blind readers. We investigated whether a PDA was mentioned on the initial CT reading. Correct diagnosis of PDA was made in all patients with group 1 (n = 42). In contrast, only 13.7% were correctly diagnosed in group 2. All cases of missed PDA in group 2 were also missed by two blind readers. It is important to realize that the diagnostic accuracy of silent PDA is poor on the chest CT with 3 mm slice-thickness. Thus, use of axial CT images with the thinnest slice-thickness and multi-planar reformatted images (i.e., sagittal and coronal images) may be one way to reduce the number of missed PDA.


Assuntos
Permeabilidade do Canal Arterial , Permeabilidade do Canal Arterial/diagnóstico por imagem , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
12.
J Virol ; 95(16): e0079921, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34105998

RESUMO

Multiple host proteins affect the gene expression of Kaposi's sarcoma-associated herpesvirus (KSHV) during latent and lytic replication. High-mobility group box 1 (HMGB1) serves as a highly conserved chromosomal protein inside the cell and a prototypical damage-associated molecular pattern molecule outside the cell. HMGB1 has been shown to play a pathogenic role in viral infectious diseases and to regulate the lytic replication of KSHV. However, its functional effects on the KSHV life cycle in KSHV-infected cells have not been fully elucidated. Here, we explored the role of intracellular and extracellular HMGB1 in KSHV virion production by employing CRISPR/Cas9-mediated HMGB1 knockout in the KSHV-producing iSLK BAC16 cell line. Intracellular HMGB1 formed complexes with various proteins, and the abundance of HMGB1-interacting proteins changed during latent and lytic replication. Moreover, extracellular HMGB1 was found to enhance lytic replication by phosphorylating JNK. Of note, the expression of viral genes was attenuated during lytic replication in HMGB1 knockout iSLK BAC16 cells, with significantly decreased production of infectious virions compared to that of wild-type cells. Collectively, our results demonstrate that HMGB1 is an important cellular cofactor that affects the generation of infectious KSHV progeny during lytic replication. IMPORTANCE The high-mobility group box 1 (HMGB1) protein has many intra- and extracellular biological functions with an intricate role in various diseases. In certain viral infections, HMGB1 affects the viral life cycle and pathogenesis. In this study, we explored the effects of HMGB1 knockout on the production of Kaposi's sarcoma-associated herpesvirus (KSHV). HMGB1 knockout decreased virion production in KSHV-producing cells by decreasing the expression of viral genes. The processes by which HMGB1 affects KSHV production may occur inside or outside infected cells. For instance, several cellular and viral proteins interacted with intracellular HMGB1 in a nucleosomal complex, whereas extracellular HMGB1 induced JNK phosphorylation, thereby enhancing lytic replication. Our results suggest that both intracellular and extracellular HMGB1 are necessary for efficient KSHV replication. Thus, HMGB1 may represent an effective therapeutic target for the regulation of KSHV production.


Assuntos
Regulação Viral da Expressão Gênica , Proteína HMGB1/metabolismo , Herpesvirus Humano 8/fisiologia , Vírion/metabolismo , Linhagem Celular Tumoral , Técnicas de Inativação de Genes , Proteína HMGB1/genética , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/metabolismo , Humanos , Nucleossomos/metabolismo , Regiões Promotoras Genéticas , Transdução de Sinais , Proteínas Virais/genética , Ativação Viral , Replicação Viral
13.
Int J Clin Pract ; 75(8): e14206, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33950544

RESUMO

BACKGROUND: Hand hygiene is paramount in preventing healthcare-associated infections in medical environments and the spread of infectious diseases in non-medical environments. AIMS: This study used a randomised controlled trial to investigate the effects of a tea tree (Melaleuca alternifolia) oil disinfectant on hand disinfection and skin condition. METHODS: A tea tree oil group received 5 mL of 10% tea tree oil disinfectant mixed in a ratio of 2:2:1:15 of Melaleuca alternifolia oil, solubiliser, glycerin and sterile distilled water. Data collection took place between April 9 and April 13, 2018. The subjects were 112 healthy adults. An alcohol group received 2 mL of a gel-type hand sanitiser comprising 83% ethanol used without water; a benzalkonium chloride group received 0.8 mL of a foam-type hand sanitiser containing benzalkonium chloride used without water and a control group received no treatment. Subjective skin condition, transepidermal water loss and adenosine triphosphate were assessed, and a microbial culture test was performed following treatment. RESULTS: The general characteristics and the pretreatment dependent variables did not differ significantly by group. Posttreatment adenosine triphosphate log10 values significantly differed across all four groups (F = 3.23, P = .025). Similarly, posttreatment bacterial density log10 values differed significantly across the tea tree oil, alcohol, benzalkonium chloride and control groups (F = 91.71, P < .001). CONCLUSION: The study confirmed that tea tree oil disinfectant is effective for hand disinfection. Accordingly, tea tree oil disinfectants may be introduced to nursing practice as a new hand hygiene product to prevent and reduce healthcare-associated infections.


Assuntos
Desinfetantes , Higiene das Mãos , Óleo de Melaleuca , Adulto , Desinfetantes/farmacologia , Humanos , Chá , Óleo de Melaleuca/farmacologia , Árvores
14.
Int J Mol Sci ; 22(7)2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33805189

RESUMO

Exposure to particulate matter (PM) is becoming a major global health issue. The amount and time of exposure to PM are known to be closely associated with cardiovascular diseases. However, the mechanism through which PM affects the vascular system is still not clear. Endothelial cells line the interior surface of blood vessels and actively interact with plasma proteins, including the complement system. Unregulated complement activation caused by invaders, such as pollutants, may promote endothelial inflammation. In the present study, we sought to investigate whether urban PM (UPM) acts on the endothelial environment via the complement system. UPM-treated human endothelial cells with normal human serum showed the deposition of membrane attack complexes (MACs) on the cell surface via the alternative pathway of the complement system. Despite the formation of MACs, cell death was not observed, and cell proliferation was increased in UPM-mediated complement activation. Furthermore, complement activation on endothelial cells stimulated the production of inflammation-related proteins. Our results revealed that UPM could activate the complement system in human endothelial cells and that complement activation regulated inflammatory reaction in microenvironment. These findings provide clues with regard to the role of the complement system in pathophysiologic events of vascular disease elicited by air pollution.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Ativação do Complemento , Proteínas do Sistema Complemento/metabolismo , Células Endoteliais/metabolismo , Inflamação/metabolismo , Vasos Sanguíneos/patologia , Morte Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Citocinas/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Material Particulado/efeitos adversos , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/metabolismo
15.
J Microbiol ; 59(5): 522-529, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33877577

RESUMO

Extracellular vesicles (EVs) play a crucial role in cell-to-cell communication. EVs and viruses share several properties related to their structure and the biogenesis machinery in cells. EVs from virus-infected cells play a key role in virus spread and suppression using various loading molecules, such as viral proteins, host proteins, and microRNAs. However, it remains unclear how and why viruses regulate EV production inside host cells. The purpose of this study is to investigate the molecular mechanisms underlying EV production and their roles in Kaposi's sarcoma-associated herpesvirus (KSHV)-infected cells. Here, we found that KSHV induced EV production in human endothelial cells via Rab-27b upregulation. The suppression of Rab27b expression in KSHV-infected cells enhanced cell death by increasing autophagic flux and autolysosome formation. Our results indicate that Rab27b regulates EV biogenesis to promote cell survival and persistent viral infection during KSHV infection, thereby providing novel insights into the crucial role of Rab-27b in the KSHV life cycle.


Assuntos
Vesículas Extracelulares/metabolismo , Infecções por Herpesviridae/metabolismo , Herpesvirus Humano 8 , Proteínas rab de Ligação ao GTP/metabolismo , Autofagia , Morte Celular , Sobrevivência Celular , Células Endoteliais/virologia , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/genética , Humanos , MicroRNAs/metabolismo , Nanopartículas , Regulação para Cima , Proteínas Virais/metabolismo
16.
Soft Matter ; 17(13): 3700-3708, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33683277

RESUMO

A concentration gradient in an aqueous solution is a promising source of energy that can be converted into electrical energy by an ion-exchange polymer membrane. In concentration-gradient energy harvesters, ion transport through nanoporous channels is an emerging approach to enhance the energy conversion efficiency. Since massive but selective ion transport could be realized through nanochannels, the theoretical calculations predicted that nanoporous membranes can extract significantly larger energy than the conventional non-structured membranes. In this regard, scientists in the field have attempted to produce nanoporous membranes on a macroscopic scale based on 1D, 2D, and 3D materials. However, the fabrication of nanoporous membranes is often accompanied by technical difficulties, which entails high production cost, low throughput, and poor scalability. In this study, we took advantage of the self-segregating properties of block copolymers (BCPs) to address these issues. In particular, the non-solvent-induced phase separation method has been utilized to produce three-dimensionally interconnected nanopores within BCP membranes. In addition, the neutral BCP nanopores' surface was modified with positive charges to allow selective diffusion of anions in concentration-gradient cells. By mounting the porous BCP membranes between two aqueous solutions with different concentrations, we studied the BCP-membrane-mediated energy-harvesting performance.

17.
Pathogens ; 9(4)2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32260199

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) modulates the immune response to allow the virus to establish persistent infection in the host and facilitate the development of KSHV-associated cancer. The complement system has a central role in the defense against pathogens. Hence, KSHV has adopted an evasion strategy for complement attack using the viral protein encoded by KSHV open reading frame 4. However, despite this defense mechanism, the complement system appears to become activated in KSHV-infected cells as well as in the region surrounding Kaposi's sarcoma tumors. Given that the complement system can affect cell fate as well as the inflammatory microenvironment, complement activation is likely associated with KSHV pathogenesis. A better understanding of the interplay between KSHV and the complement system may, therefore, translate into the development of novel therapeutic interventions for KSHV-associated tumors. In this review, the mechanisms and functions of complement activation in KSHV-infected cells are discussed.

18.
Int J Mol Sci ; 21(2)2020 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-31963761

RESUMO

The demyelinating diseases of the central nervous system involve myelin abnormalities, oligodendrocyte damage, and consequent glia activation. Neurotoxicant cuprizone (CPZ) was used to establish a mouse model of demyelination. However, the effects of CPZ on microRNA (miRNA) expression and behavior have not been clearly reported. We analyzed the behavior of mice administered a diet containing 0.2% CPZ for 6 weeks, followed by 6 weeks of recovery. Rotarod analysis demonstrated that the treated group had poorer motor coordination than control animals. This effect was reversed after 6 weeks of CPZ withdrawal. Open-field tests showed that CPZ-treated mice exhibited significantly increased anxiety and decreased exploratory behavior. CPZ-induced demyelination was observed to be alleviated after 4 weeks of CPZ treatment, according to luxol fast blue (LFB) staining and myelin basic protein (MBP) expression. miRNA expression profiling showed that the expression of 240 miRNAs was significantly changed in CPZ-fed mice compared with controls. Furthermore, miR-155-5p and miR-20a-5p upregulations enhanced NgR induction through Smad 2 and Smad 4 suppression in demyelination. Taken together, our results demonstrate that CPZ-mediated demyelination induces behavioral deficits with apparent alterations in miRNA expression, suggesting that differences in miRNA expression in vivo may be new potential therapeutic targets for remyelination.


Assuntos
Cuprizona/efeitos adversos , Doenças Desmielinizantes/psicologia , Comportamento Exploratório/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Animais , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/genética , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/efeitos dos fármacos , MicroRNAs/genética , Teste de Desempenho do Rota-Rod
19.
FASEB J ; 34(2): 2944-2957, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31908024

RESUMO

Mitochondrial quality control maintains mitochondrial function by regulating mitochondrial dynamics and mitophagy. Despite the identification of mitochondrial quality control factors, little is known about the crucial regulators coordinating both mitochondrial fission and mitophagy. Through a cell-based functional screening assay, FK506 binding protein 8 (FKBP8) was identified to target microtubule-associated protein 1 light chain 3 (LC3) to the mitochondria and to change mitochondrial morphology. Microscopy analysis revealed that the formation of tubular and enlarged mitochondria was observed in FKBP8 knockdown HeLa cells and the cortex of Fkbp8 heterozygote-knockout mouse embryos. Under iron depletion-induced stress, FKBP8 was recruited to the site of mitochondrial division through budding and colocalized with LC3. FKBP8 was also found to be required for mitochondrial fragmentation and mitophagy under hypoxic stress. Conversely, FKBP8 overexpression induced mitochondrial fragmentation in HeLa cells, human fibroblasts and mouse embryo fibroblasts (MEFs), and this fragmentation occurred in Drp1 knockout MEF cells, FIP200 knockout HeLa cells and BNIP3/NIX double knockout HeLa cells, but not in Opa1 knockout MEFs. Interestingly, we found an LIR motif-like sequence (LIRL), as well as an LIR motif, at the N-terminus of FKBP8 and LIRL was essential for both inducing mitochondrial fragmentation and binding of FKBP8 to OPA1. Together, we suggest that FKBP8 plays an essential role in mitochondrial fragmentation through LIRL during mitophagy and this activity of FKBP8 together with LIR is required for mitophagy under stress conditions.


Assuntos
Fibroblastos/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Estresse Fisiológico , Proteínas de Ligação a Tacrolimo/metabolismo , Animais , Células HEK293 , Células HeLa , Humanos , Camundongos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/genética , Proteínas de Ligação a Tacrolimo/genética
20.
Neurotox Res ; 37(3): 732-742, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31916130

RESUMO

Myelin abnormalities, oligodendrocyte damage, and concomitant glia activation are common characteristics of demyelinating diseases of the central nervous system. Administration of the neurotoxicant cuprizone (CPZ) has been extensively used to establish a reproducible mouse model of demyelination. However, its effects on myelin-related gene expression have not been sufficiently explored. In the present study, we used the Affymetrix Mouse Gene 2.0 ST Array to analyze the changes in gene expression profiles. Comparative gene expression profiling in age-matched C57BL/6 mice administered with 0.2% CPZ and with normal diet, revealed that the expression of 1655 genes was significantly changed in CPZ-fed mice with a fold change ≥ 1.5. Our results demonstrated that CPZ-induced demyelination induces apparent alterations in the expression of most of the myelin-related genes, including the 6 key genes MBP, MAG, and MOG and GFAP, CXCR4, and NgR, which were observed to be downregulated and upregulated, respectively, suggesting that the differences in gene expression in vivo could serve as potential therapeutic targets for remyelination.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cuprizona/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/genética , Expressão Gênica , Bainha de Mielina/genética , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Bainha de Mielina/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Transcriptoma
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